Interpretive Summary: Dust emissions from wind erosion on disturbed soils are very common in many regions around the world. Recently, concern for the health and climatic impact of dust aerosols has produced increased interest in this subject. Field studies of suspended dust produced during intense wind storms are difficult and few studies have been reported. Efforts are now underway to develop equipment and methods of analysis of dust aerosols under more controlled laboratory conditions. The dust analysis system described in this study allows us to make clean analyses of the physical and chemical properties of small samples of soil. These analyses are needed to identify the source of the suspended dust aerosols. This information is cricital because knowledge of the aerosol source will facilitate the development of sound strategies to reduce airborne dust, producing a cleaner and healthier environment.

Technical Abstract:
Dust emissions from wind erosion on disturbed soils are very common in many regions around the world. Recently, concern for health and climatic impact of dust aerosols has produced increased interest in this subject. Field studies of suspended dust produced during intense wind storms are difficult and few studies have been reported. Efforts are now underway to develop equipment and methods of analysis of dust aerosols under more controlled laboratory conditions. This preliminary study tests the potential and reliability of a new system to generate and analyze dust plumes under controlled conditions. We evaluated the effect of varying sample mass, soil texture, and aggregate size on 10 minute average PM10 concentration. We tested fine sand, loam, and sandy clay loam soils using 25, 50, 75, and 100 g aggregate samples. Each test was performed on the following aggregate size classes: <0.60 mm, 0.6-0.9 mm, 0.9-2.0 mm, 2.0-6.4 mm, and 6.4-19.0 mm. The amount of airborne PM10 dust increased as the sample size increase for all aggregate sizes tested. Mean PM10 concentrations varied from approximately 5300 ug/m3 for 25 g samples to 21000 ug/m3 for 100 g samples. The airborne PM10 concentration was also affected by soil texture (Figure 2b). As expected, the fine sand soil texture (with the least clay proportion) generated the lowest PM10 concentration (8200 ug/m3). PM10 concentration variation according to aggregate size showed the same general trend for all soil textures as well as for all sample sizes. We conclude the system has great potential to produce, sample, and analyze dust plumes in the laboratory.